Enabling xplink in the runtime environment and compiling
applications
with xplink enabled improves performance in z/OS® V1R2.
- For best
performance, use the LPALSTxx parmlib member to ensure that LE
and C++ runtimes are loaded into LPA, as shown in the following example:
Example:
sys1.parmlib(LPALSTxx):
********************************* Top of Data ********************
USER.LPALIB,
ISF.SISFLPA, SDSF
CEE.SCEELPA,
LANGUAGE ENVIRONMENT
CBC.SCLBDLL, C++ RUNTIME
.
.
.
******************************** Bottom of Data ******************
- Ensure that the Language
Environment® data sets, SCEERUN
and SCEERUN2, are authorized to enable xplink.
For processes that
run the
client ORB, since they start the JVM, must run with xplink (on).
For best
performance, compile applications that use JNI services with xplink
enabled.
Compiling applications with xplink enabled improves performance in z/OS V1R2.
As
you move from z/OS V1R2
to z/OS V1R6
you should experience additional performance improvements when all
of the
LE services calls are xplink enabled.
- Ensure that you
are NOT using the following options during production:
- RPTSTG(ON)
- RPTOPTS(ON)
- HEAPCHK(ON)
- Turn LE heappools
on.
If you are running a client on z/OS,
setting
the following: SET LEPARM='HEAPP(ON)' in a shell
script,
turns on LE heappools, which should improve the performance of the
client.
- Refer to Fine tuning the LE heap
Customization Note: Do not modify LE parameters
without consulting IBM® support. The LE parameters are
set internally to
ensure the best possible performance of the WebSphere® Application
Server, which
is the main LE application running in the address space. If you need
to add
or change LE parameters, make sure that you work with the IBM WebSphere support
team to ensure that the internally set parameters are not compromised.
The
appropriate interface for making these changes is through the PARM= parameter
of the EXEC PGM=BPXBATSL statement in the startup
JCL.